Neonatal Intensive Care UnitChildren's Hospital

Tromethamine (THAM(R))

Disclaimer to the On-line Edition
This Manual has been designed for use in the NICU at London Health Sciences Centre (LHSC), London, Ontario, Canada, and represents clinical practice at this institution. The information contained within the Manual may not be applicable to other centres. If users of this Manual are not familiar with a drug, it is recommended that the official monograph be consulted before it is prescribed and administered. Any user of this information is advised that the contributors, Editor and LHSC are not responsible for any errors or omissions, and / or any consequences arising from the use of the information in this Manual.

Tromethamine (THAM(R))


  • used for the treatment of severe metabolic acidosis, primarily in infants with hypercarbia or hypernatremia
  • NOT indicated for the management of metabolic acidosis associated with bicarbonate deficiency (renal tubular acidosis)


  • THAM is a highly alkaline, sodium-free organic amine alkalizing agent
  • THAM binds with hydrogen ions to form bicarbonate and a cationic buffer which is excreted in the urine
  • 1 mM of THAM can buffer no more than 1 mM of CO2
  • PCO2 may decrease slightly after treatment
  • THAM is rapidly eliminated by glomerular filtration

Side Effects

  • respiratory depression may occur (maintain assisted ventilation)
  • urine flow and electrolyte content of urine may increase because of the osmotic diuretic action of THAM
  • tissue necrosis from infiltration and extravasation
  • phlebitis and thrombosis at injection site
  • transient hypocalcemia
  • hyperkalemia and hypoglycemia have been reported
  • avoid infusion through low umbilical vein catheters (UVC) (increases risk of hepatic necrosis)
  • May be given through a UVC when the line tip is certain to be in the UVC or right atrium.
  • Do NOT infuse via UAC catheters
  • do not use in patients who are anuric, uremic or who have chronic respiratory acidosis


  • monitor IV site closely for signs of extravasation
  • monitor urine output, serum glucose, potassium and calcium


  • infuse into as large a vein as possible - a central vein is preferred
  • the appropriate dose of tromethamine is arbitrary based on minimizing the osmotic challenge while maximizing the buffering capacity
    1. Standard IV dose of 0.3 M undiluted solution:
      • 1-2 mmol/kg/dose (3.3-6.6 mL/kg/dose)
        (Maximum rate = 1 mL/min)


    2. Dose (mL) of 0.3 M undiluted solution:
      • Weight (kg) x Base Deficit (mmol/L)
        (Maximum Rate = 1 mL/min)

  • administer undiluted by slow IV infusion through a large vein

    maximum rate = 1 mL/min
    1. Continuous Infusion:
      • 2-3 mL/kg/h
      • maximum amount : 33-40 mL/kg/day
      • may dilute to 10-40% with 5% DEX/WATER


  • 0.3 M solution (0.3 M = 0.3 mMol/ml)
  • 1 mmol = 3.3 ml of 0.3 M solution


  1. MICROMEDEX(R) healthcare series, vol 116. Greenwood Village, Colorado: Thomson, Expires 6/2003.
  2. Taketomo CK, Hodding JH, Kraus DM. Pediatric dosage handbook; 9th ed. Hudson, OH: Lexi-Comp, 2002.
  3. Young TE, Mangum B. Neofax, 13th ed. Raleigh, NC: Acorn, 2000.
  4. Zenk KE. Neonatal medications & nutrition. Santa Rosa, CA: NICU, 1999.
  5. Roberts RJ. Drug Therapy in Infants. 1984. WB Saunders Company. Toronto.
  6. Phelps SJ (editor). Pediatric Injectable Drugs. 6th Ed. 2002. American Society of health- System Pharmacists. Bethesda,MD.

    Prepared: 16 September 2003
    Venita Harris (Pharmacy Resident), David Knoppert

    Last Uploaded: Thursday, 26-May-2011 00:53:49 EDT